Block system for railways.



G. W. NISTLB. E. INSKIP & B. W. BRADY.V

BLOCK SYSTEM POR RAILWAYS.

APPLIoATxoN FILED Nov. 1s, 1901;

Patented July 6, 1909.

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BLOCK SYSTEM FOR RAILWAYS. APPLIGATION rum Nov11s, 1907.

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G. W. NISTLE, E. INSKIP 6v B. W. BRADY. BLOCK SYSTEM FOB BAILWAYS.

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926,871 8. Patented July 6, 1909.

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UNITED sTArEs PArENT oEEIcE.

GEORGE W. NISTLE, OF NORTH MUSKEGON, MICHIGAN, AND EDWARD INSKII AND BERNARD W. BRADY, OF CHICAGO, ILLINOIS.

BLOCK SYSTEM FOR BAILWAYS.

To all whom it may concern:

Be it known that we, GEORGE W. NIs'rLE, residing at North Muskegon, in the county of Muskegon and State of Michigan, and ED- WARD INsKiP and BERNARD W. BRADY, residing at Chicago, in the county of Cook and State of Illinois, citizens of the United States, have invented certain new and useful Improvements in Block Systems for Railways, of which the following is a speciiication.

This invention relates to improvements in block systems, and refers more particularly to improvements in a system of that general type 1n which mechanism located along the track coperates with mechanism upon the train to automatically arrest the latter in case the train be sent into a block, the block mechanism of which is set at danger.

The salient object of the present invention is to provide a system which is completely automatic in its arresting functions and of reliable construction and operation, thereby eliminating the ersonal equation to the greatest practicab e extent and reducing the danger factor to a minimum.

Other objects of the invention are to provide simple and effective mechanism for cooperating with the air brake system with which nearly all trains are now equip ed and whereby said air brake mechanism is rought into operation automatically in case the block conditions are such that this should be done; to provide an improved type of track lever which constitutes an important factor in simplifying such systems and specifically so in carrying out the system herein described; to provide a system so organized that it is not functionally disarranged or disordered in case a train or car should be made 'to traverse the track backwardly to provide Specification of Letters Patent.

Application filed November 18, 1907.

Patented July 6, 1909.

Serial No. 402,610.

taken on line 4--4 of Fig. 2 and looking in the direction of the arrows; Fig. 1 is a detail in side elevation of the controlling wheel and associated parts and their mountings; Figs. 5, 6 and 7 are detail side elevations of the different track instruments which cooperate with the controlling wheel; Figs. 8 and 9 are cross sectional details taken on the lines 8 8 and 9 9, respectively, of Figs. 5 and 6; Fig. 10 is a front end elevation of the track instrument shown in Fig. 6.

In carrying the present invention into effect, we employ a novel type of circuit controlling track instrument, each of which in,- struments has as its main feature a lever carrying contact making devices, pivoted between its ends and provided with two or more tread surfaces inclined relatively to each other so that as the lever is traversed by a wheel it will be oscillated and left in one position or another, depending upon the direction of traverse of the wheel and direction of inclination of said tread surfaces. Sets of these track instruments, varying somewhat in construction but all of the same general ty e, are located along the rails of the railroa in position to be encountered by a controlling wheel carried in some suitable manner by some part of the train, and this controlling wheel isI under certain conditions, raised or forced upwardly by the track instruments, and thereby cause to vent the train pipe of the automatic air brake mechanism of the train, and thus bring about the arresting of the latter.

In the diagram, A designates as a whole the railroad track, T a train, and these shown diagrammatically, and C, D, D and E track instruments, which together constitute an operative set.

Inasmuch as the several track instruments are differently constructed, and these differences involve somewhat di'fferent operations, the construction of said instruments will 'first be described.

Referring to Fig. 2, the instrument there shown is that designated C. This instrument comprises a suitable base plate 15 adapted to be secured to a cross tie or other suitable support upon the roadbed, and constitutes a pivot support for the main lever of the instrument 16, being to this end provided with a standard portion 17 to which the lever is pivoted as indicated at 1S. The

lever lo is dcsirably made of angle iron, so as to be both light and strong, and it is bent to provide oppositely (.IOWn\\far lly inclined top tread surfaces 19, 1Q', at its end, and downwardly inclined converging intermediate tread portions 20, The lever is so supported, relatively to the line of travel of the controller wheel which actuates the lever, that it will be oscillated by the traverse of the wheel thereover. This lever may stand in either of its two positions when encountered by the controller wheel, t'. a. with its rear end elevated or with its forward end elevated. In the latter instance the controller wheel will simply depress the forward end, while in the former case if the rear end be elevated the controller wheel will Yfirst depress the rear end and thereafter depress the forward end, assuming, of course, that the wheel traverses it in the usual forward direction.

The position of the lever is positively controlled by either one of two magnet-s and M and cooperating latch mechanisms, and in addition to the magnet control the rear end of the lever is weighted, as indicated at 21, so that the lever will return to a normal position by gravity when not held by one or the other of the latches.

Describing said latch mechanisms, both being alike, and referring to Fig. 3, upon the side of the lever lo toward the magnet M or M is mounted a latch block 22 having a shoulder 23 with which is adapted to cooperate a latch 24 pivoted at its lower end, as indicated at 25, and carrying an armature 2o which is acted upon by the magnet. A spring 27 interposed between the latch and the head of the magnet spool tends to press the latch away from the magnet and into engagement with the latch block 22.

The two latch mechanisms are similarly disposed, and each tends to hold its own end of the lever locked positively in uplifted position, but w ien one end of the lever is latched up the opposite end is, of course, depressed. below the latching position.

In Fig. 5 is shown the instrument designated D in the diagram. The general construction and shape of this lever is, or may be, precisely the same as that of the instrument C. It is similarly mounted on the base l5 and weighted at its rear end, as indicated at 21, so as to tend to return it to a normal position. This .instrument is employed for momentarily closing a circuit while the controller wheel is passing over its lever 28. To this end the forward end of the lever carries a contact plate 29, insulated from the body of the lever and adapted to cooperate with a pair of plates 30 mounted upon a suitable 'ixed support 31. below the lever; the relative arrangement of these parts being shown clearly in Figs. 5 and 8.

In Fig. o is shown the instrument desigessere nated D in the diagram. The lever 32 ll this instrument is, or may be, of the same shape and construction as that of the instrumcnt D, and said lever is similarly mounted upon a suitable base The lever 32 is provided at its rear end with an insulated contact plate 34 adapted to cooperate with. a pair of stationary plates 35 mountedl upon the base frame 33, whilel the forward end of the lever is provided with two insulated contact plates (see Fig. lo) 36 and. 37, adapted to cooperate with corresponding pairs of stationary plates and 39, respectively, also mounted on the base frame 33, as seen clearly in Figs. o and l0.

The lever D is provided with a friction latch mechanism adapted to hold the lever yieldingly in either of its two positions in which it happens to be left, lhis friction latch mechanism comprises a. magnet 7a arranged to act upon a pivoted latch member 40 carrying an arniature 41 and provided with a conical or double inclined ei'igaging end 42 which cooperates with corres} .indingly shaped recesses, as 43 and 44, formed in the side face of the lever and at suitable peints corresponding to the two positions of the lever. The latch is held normally in cngagement with the lever by means of an expansion spring 45 interposed between the latch and head of the magnet spool.

ln Fig. T is shown the instrument E. This instrument is in construction ge erally similar to the instrument D just described, having a similarly shaped lever 4o supported on a suitable base 47, but carrying at its front end a single Contact plate 4S only. This plato cooperates with a pair of stationai y plates 49 mountedV upon the bz This instrument is also controlled by a l tion latch, but said latch in the preferred construction shown consists simply of a spring arm 50 having its lower end rigidly mounted upon the base frame 47 and provided at its upper end with a. conical engaging point similar to the point 42 of the iustrument D and similarly adapted to ecoperate with recesses 5l and 52 in the side of the lever. inasmuch as this instrument is to be shifted positively from one position to the other, it is unnecessary to provide means `cle,si; ,ri,ated as a whole 53, and which in turn carries a lever 54 pivotally mounted between its ends, as indicated at 55. n pipe 5o connected with, and leading from, the air train-pipe of the train, extends through a suitable block or support 57 upon the frame 53 and terminates in a cap 58 which is nor- Cir mally held upon the pipe so as to close and seal the latter by means of an upright lever' 59 pivoted upon the frame, as indicated at 60. This lever is held in position to retain the cap 58 by an extension 61 of the lever 54; the arrangement being such that when this end of the lever is depressed it releases the level' 59 and vents the train-pipe. Upon the longer end of the lever 54 is mounted the controller wheel 62, which cooperates with the several levers of the track instrument hereinbefore described. This controller wheel is provided with a relatively wide tread of sufficient width to simultaneously engage two of the levers of the track instrument which are sometimes arranged in overlapped relation to each other', as will hereinafter appear, and the wheel is held against rising until it encounters a lever which is held positively in fixed position by a relatively stif spring 63 mounted upon the frame 53 and bearing upon the upper side of the lever 54. When the controller wheel has been lifted so as to release the lever 59, vent the train-pipe and so apply the brakes and arrest the train, the parts associated with the controller wheel will be restored to their normal positions manually by the trainmen.

The circuits of the system which utilizes the mechanism just described will now be traced.

Referring to diagrammatic Fig. 1 the system is therein shown as organized for controlling a single way track, i. c., a track over which the trains normally pass in one direction only, as is usual where double tracks are employed. lt is to be observed that the several contact levers at the left-hand end of the first block occupy the positions (diagrammatically) which correspond to the train having fully entered said block in passing from left to right.

The several levers and their' magnets are designated by the same numerals used in describing these mechanisms.

At each end of the block are arranged four levers D, C, D, and E and also a circuit controlling lever E', one only being shown in the diagram. The levers C serve as blocking levers and are respectively controlled by the magnets M and M at either end thereof. The arrangement is such that either end of one of these levers C may be set in blocking or danger' position to prevent the 1passage of the train, by the de'e'nergization o the magnets M and M as heretofore described. These magnets are normally energized, i. e. when the block is :in cleared position.

Describing now the circuits which control the magnets M and referring to the one at the forward end of the block, the circuit connections being duplicated for the magnet M at the rear, a normally closed circuit which controls this forward magnet M extends from line L by way of conductors 64 through the windings of the forward. magnet M to conductor 69 thence by way of branch conductor 7 0 to the rear contacts of the rear lever D, thence by conductors 71 to the contacts of the lever E at the forwardfend of the block to ground at 73 by Way of conductor 72. Inasmuch as the rear end of the lever D and the forward end of lever E are normally depressed so as to close their contacts, the magnet M is obviously normally energized. It will thus be seen that the opening of the rear contacts of either lever D or the contacts of lever E by the passage of the controller wheel, will denergize the magnet M and place the rear end of the lever C in blocking position.

ln order that the magnets M may be energized independently of the action of the levers D and E', we provide another controlling circuit as follows: from line L to conductor 64 through the windings of magnet M as heretofore described thence to a branch conductor 65 to the contacts of the lever D to ground at 67 by way of conductor 66. This circuit is normally o en through the contacts of the lever D whic i it will be remembered has its rear end depressed by gravity.

It is to be noted that the rear end of lever C overlaps the forward end of the instrument D, so that while the front end of the latter is depressed by the controller wheel and the magnet M thus energized and its latch withdrawn, the controller wheel may engage and depress the rear endv of the lever' C in the event the latter does not already occupy this position.

Describing now the circuits which energize the'magnets M and referring to the one at the rear of the block, it being noted that the circuit connections for the forward magnet M are exactly similar, the circuit which controls the rear magnet M may be traced as follows: from line L to conductor 68 through the windings of magnet M, thence by way of branch conductor 7 0 to rear contacts of the adjacent lever D, from these contacts to conductor 7l to the forward end of the block, to the contacts of lever E and thence to ground at 73 by way of conductor 72. inasmuch as the rear end of the levers D and the forward end of the levers E are normally depressed the magnets M are obviously normally energized and their respective latches withdrawn. The lever E and the ground 73 ofthe circuit which. controls the forward magnet M are not shown in the diagram but are arranged in exactly the same manner as just described.

It might be here noted that the magnets M may also be energized by placing on the ground 67, but inasmuch as these circuits are only momentarily closed, i. c. during the time the controller wheel is passing over one of the levers D, and inasmuch as they pei'- form no electrical function iii the system, they need not be described in detail.

The levers D are controlled by the magnets mv and their corresponding latch mechanisms. It will be remembered that in case the forward end of one of the levers D was depressed it was held in that position by means of the friction latch mechanism 40 (see Fig. 9) and there held until its magnet m was energized and the latch withdrawn.

Describing now the circuit connections which control these respective magnets m and tracing the circuit connections of the rear magnet m, the circuit extends from line L by way of conductor 7 4 through the windings of the magnet m to conductor to the forward end of the block thence to the contacts of lever E to the conductor 76, from conductor 76 to one set of the contacts on the front end of the forward lever D to conductor 77 thence by way of conductor 71 to the contacts of lever E and ground 73 in the block ahead. This circuit is normally open through the forward contacts of lever D in the advance end of the block, inasmuch as in the normal position of this lever its rear end is depressed and the forward end elevated. 1t will thus be seen that as the conductor wheel rises over either end of the levers D the latch mechanism will hold the forward end of the lever in depressed position inasmuch as the controlling magnet m will be denergized. However, when the train passes out of the block it will depress the forward end of lever D at the forward end of the block which will close the circuit just traced thus energizing the magnet fm, at the rear, withdrawing its latch mechanism and permitting the rear lever D to return to normal position. This clears the block as will hereinafter more clearly appear.

The levers E and E are adapted for use in case a train is backing through the block and their respective functions will be more fully described hereafter.

Assuming that a train is passing forwardly through the block and has fully entered the saine as shown in the diagram, the o eration of the system is as follows; when t e train was entering the block its controller wheel first encountered and depressed the forward end of the lever D thus closed the circuit which energized the rear magnet M and withdrew the latch and permitted the controller wheel to ride over the rear end of the lever C. Tnasmuch as at this time the rear magnet M was energized and its latch withdrawn, the controller wheel could oscillate the forward end of the lever C and safely pass over this lever. When the controller wheel reached the rear lever D it found its forward end elevated and depressed the same as it passed thereover. The lever D however after the passage of the controller wheel did not ieturn to its normal position because of its friction latch mechanism, the magnet m being denergized as heretofore described.

The train now having passed safely into the block is protected from a train advancing from the rear. This resulted from the fact that when the controller wheel of the train passed over the rear lever D it depressed the forward end of said lever and latched it in that position. This opened the contacts at the rear end of this lever cutting off the ground E through and denergizing the rear magnet M. The latch mechanism of this latter magnet was now released and the blocking lever C placed in danger position.

As the train proceeded into the block the controller wheel passed over the rear lever E and oscillated the saine without however performing any electrical function inasmuch as it restored this lever to the position in which it found it.

As the train advances in the block the controlled wheel will encounter the lever E first elevating and then restoring the forward end of this lever to normal but without energizing the rear magnet M and clearing the block inasmuch as the ground at 7 3 still remains off by reason of the fact that the contacts at the rear end of the rear lever D are broken.

As the train passes out of the block in question, the controller wheel will first pass over forward lever D thus momentarily closing the second controlling circuit heretofore described which energizes the magnet M, whereupon the magnet will withdraw its latch and the controller wheel can depress the rear end of forward lever C. 1t is necessary at this time to energize the forward magnet M inasmuch as the circuit which normally keeps this magnet energized is broken at the rear contacts of the lever D at the entrance end of the block. .lf the block ahead is cleared, the magnet M controlling this lever C will be energized and the controller wheel can safely pass over the forward end of this lever C. lt might be lieie noted that as heretofore described the various magnets which control the blocking levers are normally energized when any block is in cleared position.

After the train passes over the forward lever C it next encounters the forward lever D and as it passes over the same depi'esses the forward end of the lever and elevates the rear ,end thereof. his closes the forward contacts of this lever D, putting on the ground 73 in the block ahead and closing the circuit which energizes the rear magnet m at the entrance of the block in question. This rear magnet m thereupon withdraws its friction latch releasing the rear lever D which returns to normal position by gravity. The circuit which energizes the rear magnet lv is thereupon closed through the rear contacts of rear lever D7 the latch which controls the forward end of the rear lever C withdrawn and the block again in cleared position for an advancing train.

It is thus obvious that the train will set each block to danger or blocked position as it enters the same, and clear the block just traversed as it leaves it.

As an auxiliary feature, which may or may not be employed, sema hores are arranged at the entrance to each b ock, each sema hore being designated S and controlled as fo ows: From suppl T- conductor L a conductor 78 leads to a contact carried by the front end of each lever D, adapted to engage when depressed a contact connected with a conductor 79 which leads to and. through a solenoid 8O and from thence to ground at 81. The solenoid when energized holds a semaphore arm S in danger position.

In case a train desires to back into a block the system is so arranged that the blocking levers C at either end will be set at danger after the train has backed in thus closing the block at either end. This is true of course in case the block is open when the train starts to back into the same. Assuming the block is cleared the set of levers at the forward end of the block are in their normal position, i. e. the position shown in Fig. 1 and the levers at the other end of the block are in the same osition. As a train backs into the block 1t will first encounter the lever E and as it passes over the latter opens the contacts at this lever. The lever remains in the position it is left after the train passes over it i. e. with its contacts open as heretofore described. The train passing over this lever does not perform any electrical function inasmuch as the contacts on the front end of the forward lever D are at this time open. When the train backs over .the forward lever D it first closes but immediately thereafter opens the contacts of this lever and restores the same to normal position. When the traversing member of the train reaches the forward end of lever C it will depress the latter inasmuch as the magnet M controlling the latch at this end of the lever is at this time engaged. The circuit which engages this magnet extends from line by way of conductor 68, windings of magnet M branch conductor 70, rear contacts and lever D and conductor 71 to ground at 7 3 in the block ahead. When the traversing member encounters the rear end of this lever it depresses the latter for the reason that the controlling magnet M is likewise engaged at this time and its latch withdrawn. The circuit which controls this magnet eX- tends from line L, conductor 64, windings of magnet M, conductor 69 to the rear of the block to branch conductor 7 0 to the rear contacts of rear lever D at this time closed, to conductor 71 to `ground at 73. The train proceeding in its backward direction passes over the forward lever D which however returns to normal by gravity as heretofore stated.

The train has now safely entered the block but is not protected either from a second backing train or from a train proceeding in a forwardly direction. However as the train continues to back into the block its traversing member encounters the lever E which is like the levers E, and opens the contacts at the forward end of this lever. This takes off ground 7 3 which it will be remembered is included in the circuit of the rear magnet M and the forward magnet M. These respective magnets are now denergized through the o ening of the contacts on this lever E and t ieir respective latches spring into blocking position. A train now entering the block will be unable to depress the forward end of the rear lever C, while a train backing into the block will be unable to depress the rear end of forward lever C. inasmuch as the block can never be set in cleared position as long as the contacts on lever E are open, the block remains in danger positionat both ends until the train which has backed in again moves forwardly and restores this lever E to normal position.

When the train in question has passed out of the forward end of the block it automatically restores the latter to cleared. osition. This is accomplished in exactly tie same manner as heretofore described in connection with a train passing directly through the block. It being noted that as the train passes over the lever E it closes the contacts of this lever which remain in closed position.

Assuming now that a train is attempting to back into a block, when the train is in danger position i. e. during the time when another train is still within the block, the operation. may be described a follows: When the train within the block passed over the rear lever D it opened the contacts at the rear end of this lever and set both ends of the block in danger position. This was accomplished by the fact that the rear contacts of rear lever' are included in the circuit of the rear lever M and also in the main circuit of the forward lever M as heretofore described.

The forward magnet M is thus denergized.

When the backing train as it enters the block will ass over the levers E and D and the forwarf end of lever C as heretofore described. When the traversing member however encounters the rear end of forward lever C it will be unable to depress the latter for the reason that the latch is released, the magnet M being denergized. The backing train will not of course be able to reach the lever D and put on the ground 67 to energize the magnet M inasmuch as before it reaches this lever D it must first pass over the rear end of lever C. For the sake of clearness the circuit which controls the magnet M of the forward lever' C may be traced as follows: from line Ll l) L by way of conductor 64 windings of magnet l M, conductor 69, branch conductor 70 to the rear contacts of rear leverl D (now open) to conductor 7l, thence by way of contacts of lever E to ground at 73.

Vhile we have herein shown an embodiment of our invention it is of course apparent that it could be changed in various ways without in any manner departing from the spirit of the invention.

Ne claim as our invention:

l. In a railway block system, the combination with a suitable support oll a contact lever pivoted between its ends upon said support and provided with two oppositely inclined track surlaces whereby the lever is oscillated and its position changed twice by the traverse thereover ol` a traversing member carried by a train..

ln a railway block system, the combination with a suitable support ol' a contact lever pivoted between its ends upon said support and provided with two oppositely inclined track surl'aces whereby the lever is oscillated and its position changed twice by the traverse thereover oll a traversing member carried by a train, and circuit controllingl devices controlled by said lever. l

ln a block system, a contact controlling l lever pivoted between its ends and provided with two oppositely inclined track surfaces whereby its position is changed twice by the traverse thereover ol' a traversing member carried by a train, and locking mechanism associated with said lever l'or locking it in one ol its positions.

4. ln a block system, a contact controlling lever pivoted between its ends and provided with two oppositely inclined track surl'aces whereby the lever will be oscillated and its position changed twice by the traverse thereover oll a traversing member carried by a train, and means l'or locking said contact lever against oscillation in either one olits two positions.

5. ln a block system, a blocking lever pivotally mounted between its ends and adapted to be oscillated twice by the traverse thereover ol` a traversing member carried by i a train, a locking mechanism associated with one end ol said lever l'or locking that end oll the lever against depression7 a magnet controlling said locking mechanism, and an electric circuit connected with a source oll energy including` the windings ol' said magnet. i

6. In a block system7 a blocking lever pivl otally mounted between its ends and adaptl ed to be oscillated twice by the traversel thereover olI a traversing member carried by l a train, locking mechanism associated with each end ol' said lever and adapted to lock the latter in either ol' its two positions, and a magnet associated with each locking l mechanism and controllingl the latter. l

7. ln a block system, a blocking lever provided with two oppositely inclined track surlaces and pivoted between its ends, two sets ol' self-acting locking mechanisms associated with said lever and adapted to lock the latter in either ol' its two positions, a pair ol magnets respectively associated with the two locking mechanisms and adapted to unlock the latter when energized, electric circuit connections including said magnets, and means actuated by the traverse ol a train and located at a distance l'rom said lockingl lever lor controlling said circuit connections.

8, ln a blcck"system, the combination with a length ol' track, ol' a set ol levers at each end ot' said length, each set comprising ar blocking lever pivoted between its ends, locking mechanism l'or locking the lever in either ol' its two positions, magnets lor controlling said locking mechanism, and a sec-- ond lever' pivotally supported, adapted to be actuated by the traverse thereover ol' a traversing member carried hy a train, and electrical contact devices controlled by said second lever, olI a source ol' electric current, and circuit coimections including said magnets and the contacts controlled by said contact levers whereby the contact levers control the blocking levers electrically.

t). In a, block system, the combination with a length oll track or block, ol' a I )locking lever pivoted 'between its ends and having two oppositely inclined track surl'aces whereby it oscillated twice during the traverse thereover ol' an actuating member carried by a train, electrically controlled locking mechanism associated with said lever l'or locking it in one ot its positions, a sell' returning contact-controlling lever pivotally mounted and adapted to be oscillated by the traverse thereover ol' a member carried by a train, electro-iiiagnetic means controlling the. restoration ol said contact lever to normal, a

circuit lor said latter means extending to the remote end or the block, train actuated contact devices l'or controlling the latter circuit at said remote end lol' the block, and a circuit lor actuating the locking mechanism olthe blocking lever, controlled by contacts actuated by said contact lever, whereby the return ol' the latter to normal etlects the unlocking olI the blocking lever'.

l0. ln a block system, the combination with a length ol track or block, ol a blocking lever pivoted between its ends and having two oppositely inclined track surl'aces whereby it is oscillated twice during the traverse thereover ol an actuating member carried by a train, automatically acting, electrically retracted locking mechanism associated i with said blocking lever l'or locking it in one ol its positions, a Ysell-returning contact controlling lever removably mounted and adapted to be actuated by the traverse thereover Cil ol'l a member carried by a train, automatically engaging electrically releasable retaining mechanism controlling the restoration of said contact lever to normal, a circuit for said retaining mechanism extending to the remote end ol" the block, train actuated contact devices l'or controlling the latter circuit at said remote end oli' the block, and a circuit i'or actuating the locking mechanism ol' the blocking lever, controlled by contacts actuated by said contact lever, whereby the traverse ci' a train over the contact lever places the blocking lever in blocking condition and the return oil the contact lever to normal el'lects the unlockingr of the blocking lever.

11. In a block system, the combination with a length of track or block, of a blocking lever pivoted between its ends and. having two oppositely inclined track surfaces whereby it is oscillated twice during the traverse thereover of an actuating member carried by a train automatically engaging electrically retracted locking mechanism associated with said lever for locking it in one of its positions, a source of electrical energy, normally grounded at one side, a circuit eX- tending therefrom through the magnet of said locking mechanism and to ground through two branches resv ectively controlled by levers located, one a jacent to the locking lever and the other at the remote end of the block, a self-returning electrically-releasable contact lever controlling the grounded branch of said circuit adjacent to the blocking lever, a circuit controlling the releasing mechanism of said contact lever and extending to the remote end of the block, and a train-actuated contact lever located at said remote end of the block and controlling said releasing mechanism.

12. In a block system, the combination with a length of track or block, of a blocking lever pivoted between its ends and having two oppositely inclined track surfaces whereby it is oscillated twice during the traverse thereover ol an actuating member carried by a train, automatically engaging locking mechanism associated with each end of said blocking lever, mechanisms arranged to release each of said locking mechanisms, suitable circuit connections and means located at the same end of the block with the blocking lever for temporarily energizing the magnet controlling one of said locking mechanisms, and suitable circuit connections and means located at the remote end of the block for closing a temporarily open circuit through the magnet controlling the other locking mechanism.

13. In a railway system, the combination with a suitable support, of a lever pivoted between its ends upon said support and adapted. to be cscillated twice by the traverse thereover of a traversing member carried by a train.

14. In a block system, a contact controlling lever pivoted between its ends and provided with track surfaces whereby its position is changed twice by the traverse thereover of a traversing member carried by a train, and locking mechanism associated with said lever for locking it in one of its positions.

15. In a railway system, the combination with a lever pivotally mounted between its ends, and adapted to be oscillated twice by the traverse thereover of a traversing member carried by a train, and means for yieldably holding said lever in the position in which it is left after the traverse thereover of said traversing member.

16. In a railway block system, the combination with a length of track, of a blocking lever pivotally mounted between its ends adjacent to said track, locking mechanism for limiting the depression of one end of said lever and train carried mechanism adapted to oscillate said lever into engagement with said locking mechanism.

17. In a railway system, the combination with a track and a blocking lever, of one or more train actuated contact controlling levers and a train carried lever adapted to be actuated by said blocking lever, and adapted to actuate said contact controlling levers.

18. In a railway block system, the combination with the air-brake pipe of a train, ol a lever ivotally mounted between its ends and aolapted to close the outlet of said pipe, and a second lever ivotally mountec etween its ends and a apted to lock said first lever in closed position, a traversing member carried by said second lever, means for normally holding said traversing `member in depressed. position., and blocking mechanism associated with the track for lifting said traversing member, thereby tripping the locking lever and releasing the first lever to vent the pipe.

19. In a railway block system, the combination with the air brake pi e of a train, of a pivotally mounted lever a apted to close the outlet of said pipe, a spring actuated lever adapted to lock said rst lever in closed position, and blocking mechanism associated with the track for automatically triping said locking lever to release the first ever and vent said ipe.

GE RGE W. NISTLE. EDWARD INSKIP. BERNARD W. BRADY. Witnesses:

EMILIE Rosn, FRANK L. BELKNAP. 

